Collapsible control lever

ABSTRACT

A collapsible control lever suitable for use on a motorcycle includes a handlebar mount, an intermediate section and a lever section. The intermediate section and lever section are capable of rotation with respect to the handlebar mount between a relaxed position and an actuated position in order to provide control lever functions, such as disengaging a manual clutch. The lever section is capable of rotation with respect to the intermediate section between a normal position and a fully deflected position in order to avoid damage in the event of the motorcycle overturning. The lever section may be biased to its normal position.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.09/716,539 now U.S. Pat. No. 6,393,936 filed Nov. 20, 2000, which is acontinuation-in-part of U.S. patent application Ser. No. 09/543,943 nowabandoned, filed on Apr. 6, 2000, which is a continuation-in-part ofU.S. patent application Ser. No. 09/354,065 now abandoned filed on Jul.15, 1999, the entire contents of which are hereby expressly incorporatedby reference.

FIELD OF THE INVENTION

The present application relates to control levers for vehicles. Moreparticularly, the present invention relates to a collapsible controllever suitable for use on motorcycles.

DESCRIPTION OF THE RELATED ART AND SUMMARY OF THE INVENTION

In many motorcycles the brake and/or clutch is operated by a manuallever that is mounted to the handlebar. A bowden wire or hydraulic hose,depending on whether the brake or clutch is mechanical or hydraulic,extends from the lever to a structure that is to be operated, i.e. thebrake or clutch.

Typically, the manual lever is located alongside the handgrip on thehandlebar. To operate the lever the rider places one or more fingersaround the handgrip and lever; the rider then applies a squeezing forceto the lever to rotate the lever toward the handgrip. The lever movementproduces a pulling force on the bowden wire, or a pushing force on ahydraulic plunger, again depending on the type of brake or clutch to beactuated.

One problem with conventional levers is that, due to the handlebargenerally being the most outwardly disposed portion of the motorcycle,in the event of the motorcycle falling over the end of the lever mayforcibly strike the ground causing the lever, or its mounting structure,to break. This could occur from the motorcycle being tipped from itskickstand or work stand. In another situation, the motorcycle could besubject to a crash while in motion. A manual transmission motorcycle isinoperable without a functioning clutch, therefore if the clutch leveris broken during a motorcycle race the rider will not be able to finish.In many racing events the rider must finish the race in order to scorepoints; if a rider does not complete the race the rider is given a DNF(Did Not Finish) and is awarded zero points. A single DNF may cost arider enough points to lose the championship in a series made up ofindividual races.

An attempted solution to this problem is illustrated in U.S. Pat. No.6,047,611 to Warren et al. The Warren et al. control lever assembly usesa modified lever section having two pivots. The first pivot allowssubstantially fore and aft rotation about an axis, while the secondpivot allows substantially up and down rotation about an axis. Thepurpose of the two pivots is to allow the lever to fold away such thatthe handlebar absorbs any impact from the ground as a result of themotorcycle falling over. Such a construction, however, has manydrawbacks preventing it from being widely used. The multi-pivotconstruction of Warren et al. is complex, heavy and does not performadequately in comparison with a conventional lever.

Another solution, used especially by motorcycle racers, is to modify thelever to provide a hole or notch on an outward portion of the lever. Thepurpose is to weaken the lever so that in the event of a crash the leverwill break at the weakened area. The hole or notch is positioned suchthat a portion of the lever will remain intact to allow the rider tofinish the race, however it must also be located far enough inward fromthe end of the handlebar so that the remaining portion of the lever isnot in contact with the ground when the motorcycle is on its side.Otherwise, the lever would be subject to damage in a similar manner to aconventional lever. As a result, after a crash in which the lever issevered at the weakened area, the intact portion provides little spacefor the rider's fingers to actuate the lever. Therefore, with thisapproach the lever must be replaced after the race. As crashes are afrequent occurrence in motorcycle races, this method becomes quiteimpractical.

An aspect of the present invention involves the realization of severalinherent disadvantages in a multi-pivot control lever, such as thatillustrated in Warren et al. The disadvantages with respect to aconventional control lever include reduced cable pull (or plungermovement), reduced finger grip area, and unwanted motion of the lever.

Providing multiple pivots in a control lever takes up a significantamount of space, forcing the rider's fingers to be positioned furtherfrom the lever's axis of rotation (pivot) than a conventional lever. Acontrol lever can only be positioned so far from the handlebar and stillbe comfortable for the rider to reach with his fingers. Therefore, theavailable rotational motion is limited and moving farther from the pivotreduces the amount the wire is moved relative to its sheath in a bowdenwire arrangement, or the amount the hydraulic plunger is moved in ahydraulic arrangement (generically referred to as “cable pull”). As itis desirable to keep the rotational movement required at a minimum,increasing the distance of the lever input of the rider's fingers fromthe pivot of the lever presents a disadvantage.

An additional disadvantage to the multi-pivot construction is that thespace taken up by the pivot assembly reduces the lever area availablefor the rider's fingers. As. most riders use their inner one or twofingers to control the lever, the multiple pivots illustrated in Warrenet al. decrease the most valuable portion of the lever.

The multi-pivot design as in Warren et al. includes a horizontal axis ofrotation that allows substantially vertical movement of the lever. Inorder to be useful, the resistive element in the horizontal pivot of amulti-pivot lever construction must be flexible enough to allow thelever to move if the motorcycle were to fall over while at very lowspeeds or even while standing still. This is a disadvantage because mostof the forces imparted on an off-road motorcycle are verticallyoriented, such as from rough surfaces or the motorcycle landing fromjumps. As a result, substantial vertical forces may cause undesiredmovement of the lever while the motorcycle is in use.

Accordingly, preferred embodiments of the present invention provide acollapsible control lever that inhibits breakage, avoids problems of theprior art and performs control functions as well as a conventionallever.

One aspect of the invention is a manual lever assembly for mounting on ahandlebar including a handgrip. The lever assembly includes a handlebarmount defining a gripping surface for contacting a handlebar wherein thegripping surface defines a handlebar axis. The handlebar mount defines afirst axis of rotation. The lever assembly additionally. includes anintermediate section connected to the handlebar mount so as to berotatable about the first axis between a relaxed position and anactuated position. The intermediate section defines a second axis ofrotation and an actuator retaining portion. A lever section defining afinger grip portion and having a distal end and a pivot portion isconnected to the intermediate section so as to be rotatable about thesecond axis of rotation. The lever section further has a normal positionand a fully deflected position at least approximately 120° from thenormal position. The distal end of the finger grip portion of the leversection defines a first perpendicular distance from the handlebar axiswhen the intermediate section is in a relaxed position. The distal endof the finger grip portion of the mount further defines a secondperpendicular distance from the mount when the intermediate section isin an actuated position, the first distance being longer than the seconddistance.

A further aspect of the invention is a manual lever assembly formounting on a handlebar including a handgrip. The lever assemblyincludes a handlebar mount defining a gripping surface for contacting ahandlebar wherein the gripping surface defines a handlebar axis. Thehandlebar mount defines a first axis of rotation. The lever assemblyadditionally includes an intermediate section connected to the handlebarmount so as to be rotatable about the first axis between a relaxedposition and an actuated position. The intermediate section defines asecond axis of rotation and an actuator retaining portion. A leversection defining a finger grip portion and having a distal end and apivot portion is connected to the intermediate section so as to berotatable about the second axis of rotation. The lever section furtherhas a normal position and a fully deflected position at leastapproximately 80°-90° from the normal position. The distal end of thefinger grip portion of the lever section defines a first perpendiculardistance from the handlebar axis when the intermediate section is in arelaxed position. The distal end of the finger grip portion of the mountfurther defines a second perpendicular distance from the mount when theintermediate section is in an actuated position, the first distancebeing longer than the second distance. The intermediate section and thelever section are prevented moving vertically relative to the mount.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a preferred embodiment of a motorcyclewith a collapsible control lever.

FIG. 2 is a plan view of a preferred embodiment of a collapsible controllever adapted to disengage a manual clutch assembly, shown in a relaxedposition.

FIG. 3 is a plan view of the control lever of FIG. 2, shown in anactuated position.

FIG. 4 is a cross sectional view of the control lever of FIGS. 2 and 3taken along section line 4—4 in FIG. 2.

FIG. 5 is a plan view of the control lever of FIG. 2, shown in a fullydeflected position.

FIG. 6 is a plan view of a second preferred embodiment of a collapsiblecontrol lever adapted to disengage a manual clutch assembly, shown in arelaxed position.

FIG. 7 is a cross sectional view of the control lever of FIG. 6 takenalong section line 7—7 in FIG. 6.

FIG. 8 is a plan view of the control lever of FIG. 6, shown in a fullydeflected position.

FIG. 9 is a plan view of a preferred embodiment of a collapsible controllever adapted to disengage a hydraulic clutch assembly, shown in arelaxed position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention has utility for use with a number of vehicles,including without limitation motorcycles, bicycles and other types ofall-terrain vehicles where control levers are suitable. In addition,advantages present in preferred embodiments may be realized with anumber of different control lever functions, such as for use with amanual clutch, braking systems or engine decompression systems providedto ease manual kick-starting. The clutch control lever is particularlydesirable, however, for use on an off-road motorcycle.

Referring now to FIG. 1, an off-road motorcycle, referred to generallyby the reference numeral 30, is shown. Preferably, an internalcombustion engine 32 mated to a manual transmission (not shown) ismounted into a frame 34. A rear wheel 36 is connected to the frame 34through a rear suspension system comprised of a swingarm 38 and a rearshock 40. Preferably, the rear wheel 36 is driven by the engine 32through a chain and sprocket assembly. A front wheel 42 is connected tothe frame through a front suspension system comprised of telescopingforks 44 and upper and lower fork clamps 46, 48. The fork clamps 46, 48are connected to a steering stem (not shown) that is journalled forlimited rotation about a steering axis defined by the head tube (notshown) of the frame 34.

A handlebar 50 is preferably connected to the upper fork clamp 46 forsteering of the motorcycle 30. Preferably, each end of the handlebar hasa handgrip 51 for the rider to grasp. The handlebar 50 provides asurface in which to mount a plurality of rider controls, preferablyincluding a twist-type throttle assembly, an engine stop button, a brakelever and a clutch lever 52. Additionally, certain motorcycles may alsoinclude an engine decompression lever. The decompression lever, whileengaged, lowers the compression ratio of the engine to allow for easiermanual kickstarting. Certain other motorcycles, when equipped with anelectric start feature, may include an engine start button. A typicalarrangement would place the throttle and brake lever on the right sideof the handlebar 50 (from the perspective of a rider seated on themotorcycle) and the clutch lever 52 and engine stop button on the leftside of the handlebar 50.

The motorcycle 30 also includes a pair of footpegs 54, preferablymounted to a lower portion of each side of the frame 34, on which therider may place his feet. An elongated straddle-type seat 56 is providedfor use when the rider is in a seated position. A plurality of bodyportions of the motorcycle 30 are provided, including front and rearfenders 58, 60, a gas tank 62, a pair of radiator shrouds 64 and a pairof side panels 66.

With reference to FIGS. 2-4, the clutch lever assembly 52 will now bedescribed in detail. The lever 52 is comprised generally of a handlebarmount (or perch) 68, an intermediate section 70 and lever section 72.

The handlebar mount 68 is secured to the handlebar 50 by a clampingportion 74 that extends at least partially around the handlebar and aclamp plate 76 that is preferably connected to the clamping portion 74through a pair of clamp bolts 78 (only one shown). The inner surfaces ofthe clamping portion 74 and the clamp plate 76 cooperate to form agripping surface. The handlebar mount 68 may be rotated about an axis Hdefined by the gripping surface so as to place the lever 52 in acomfortable position for the rider of the motorcycle 30.

The handlebar mount 68 extends generally in a radial direction from theaxis H terminating in a housing portion. The housing portion defines acylindrical aperture 80 through which the bowden wire, or control cable122 may pass. A pair of flange sections 82 extend outward from a centralportion of the handlebar mount 68 defining a cavity that cooperates witha portion of the intermediate section 70.

The intermediate section 70 is generally “L-shaped” with one endcomprised of a lever pivot tab 84 and the second end comprised of a pairof flange sections 86 defining a space or cavity. The lever pivot tab 84is sized and shaped to cooperate with the cavity defined by the flanges82 of the handlebar mount 68. The flanges 86 of the intermediate section70 are spaced apart sufficiently to accommodate a portion of the leversection 72. The intermediate section 70 additionally defines a cableanchor cavity suitable to exert a pulling force on a bowden wire, in awell-known manner.

The lever section 72 comprises an elongated finger grip portion 88 witha pivot portion 90 at one end and a ball end 92 at the other. Desirably,the finger grip portion is at least one (1) inch long and, preferably,is at least 3½ inches long. The pivot portion 90 is sized and shaped tocooperate with the cavity defined by the flange sections 86 of theintermediate section 70. The lever section 72 additionally has aprotruding tab portion 94 including a transversely extending threadedthrough-hole. A reach adjustment bolt 96 is threaded through the tab 94and is held in a desired depth relative to the tab 94 by a lock nut 98.

As mentioned previously, the handlebar mount 68 is secured to thehandlebar 50 of the motorcycle 30. The lever pivot tab 84 of theintermediate section 70 fits between the flanges 82 of the handlebarmount 68. The intermediate section 70 is connected to the handlebarmount 68 by a lever pivot bolt 100 that passes through correspondingapertures in each component 68, 70. Thus, the intermediate section 70 iscapable of rotation relative to the handlebar mount 68 about an axisdefined by the lever pivot bolt 100 (sometimes referred to herein as thelever pivot). FIG. 4 shows the lever pivot bolt 100 fixed by a retainingnut 102. Alternatively, the bottom flange 82 of the handlebar mountcould be provided with a threaded aperture to retain the lever pivotbolt 100. Other suitable methods of creating a rotational connection mayalso be used.

With primary reference to FIG. 4, the structure of the pivot that allowsdeflection of the lever section 72 of the clutch lever assembly 52(sometimes referred to herein as the deflection pivot) will be describedin detail. As previously mentioned, the pivot portion 90 of the leversection 72 fits within the cavity formed by the flanges 86 of theintermediate section 70. A deflection pivot bolt 104 is passed throughcorresponding apertures in the intermediate section 70 and lever section72 allowing the lever section 72 to rotate relative to the intermediatesection 70 about a deflection axis D defined by the deflection pivotbolt 104. Additionally, bushings 106 may be positioned between theintermediate section 70 and the lever section 72 to prevent wear of thecomponents 70, 72 and contamination of the pivot. Obviously, othersuitable methods of creating a rotatable joint may be used. For example,the lever section 72 could incorporate upper and lower flanges and theintermediate section 70 could form a tongue portion that fits betweenthe flanges. Similarly, the bushings 106 may be omitted or substitutedby a bearing.

A biasing assembly 108 is provided on the deflection pivot to bias thelever section 72 to a normal position. The biasing assembly 108illustrated in FIG. 4 is primarily comprised of a torsion spring 112.The torsion spring 112 is arranged coaxially with the deflection pivotbolt 104 and is separated from the intermediate section 70 by a washer114. The biasing assembly 108 also comprises a retaining spool 116,which supports the resilient torsion spring 112 from the underneath sideand centers it about the deflection axis D and a nut 110 secures thespool 116. Both ends 118, 120 of the torsion spring 112 extend axiallyfrom the body of the spring 112. One end 118 of the torsion spring 112is retained in a suitable cavity in the lever section 72 and the otherend 120 is retained in an aperture in the spool 116. With thisarrangement, the torsion spring 112 biases the lever section 72 into anormal position where the end of the reach bolt 96 abuts an edge surfaceof the intermediate section 70, as illustrated in FIG. 2. Minoradjustments to the orientation of the lever section 72 with respect tothe handlebar axis H may be made by adjusting the reach bolt 96. Ofcourse, the torsion spring 112 may be replaced by a different biasingmember, such as an extension spring, strip of spring steel, rubberstrands or surgical tubing.

A preferred handlebar mount 68, intermediate section 70 and leversection 72 are machined from aluminum. However, other suitable rigidmaterials may also be used, including steel, plastics or composites.Additionally, other methods of shaping the components may be used, suchas casting, forging or injection molding.

When constructed substantially as described above, the clutch lever 52advantageously performs normal control lever functions comparably with aconventional control lever. FIG. 2 illustrates the clutch lever 52mounted to a handlebar 50. The intermediate section 70 is in a relaxedposition wherein the ball end 92 of the lever section 72 defines a firstperpendicular distance (D_(R)) from the handlebar axis H. Theintermediate section 70 of the lever assembly 52 is adapted to retainthe end, or anchor, of a conventional bowden wire, or control cable 122.A cable adjustment mechanism 124 is provided to increase or decreasetension in the control cable 122, as is well known. To operate thecontrol lever 52, the motorcycle rider uses one or more fingers engagingthe finger grip portion 88 of the lever section 72 to rotate the lever52 toward the handlebar 50. The reach bolt 96 transfers the force inputof the lever section 72 into the intermediate section 70, causing theintermediate section 70 to rotate about the lever pivot axis L toachieve an actuated position, wherein the ball end 92 of the leversection 72 defines a perpendicular distance (D_(A)) from the handlebaraxis H. The rotation of the intermediate section 70 exerts a pullingforce on the control cable 122 and, in the present situation, disengagesa manual clutch. Obviously, the lever assembly 52 can be adapted for usewith a mechanical or hydraulic brake assembly or an engine decompressiondevice.

The construction of the deflection pivot advantageously allows the leversection 72 to rotate towards a fully deflected position (represented byΘ in FIG. 5), to reduce the likelihood of the lever 52 being damaged orbroken in the event the motorcycle 30 overturns. The biasing member 108is resistive enough to retain the lever 52 in its normal position (FIG.2) when the motorcycle is traversing rough terrain, but allows the leversection 72 to deflect upon forcibly striking an object, such as theground.

Off-road motorcycle riding, and racing in particular, results in large,substantially vertical force inputs to the motorcycle 30. These forceinputs result from the motorcycle 30 traversing rough terrain andlanding from jumps. Modem motorcycles allow racers to routinely jumpdistances of well over 100 feet, at heights of well over 30 feet. Toresist the vertical forces encountered upon landing from such heights,the deflection pivot axis D is advantageously arranged in anon-horizontal and, preferably, a substantially vertical orientation,limiting the movement of the lever section 72 to a non-vertical and,preferably, generally a horizontal plane. As a result, the lever section72, and the entire portion of the assembly which pivots about the leverpivot axis L is prevented from moving in response to vertical forceinputs, ensuring that it will remain accessible to the rider of themotorcycle 30, even upon landing from extreme heights.

In order to fully understand advantages of the present invention, it isnecessary to provide a discussion of design parameters involved withcontrol levers generally, and bowden wire clutch levers in particular.The clutch lever 52 on the motorcycle 30 functions to convert rotationalmotion of the lever 52 about its lever pivot axis L into linear motionsuitable to actuate the bowden wire, or control cable 122. The amount oflinear motion of the control cable 122 is generally referred to as the“cable pull”. A fixed minimum amount of cable pull is required tooperate the component connected to the lever 52, in the presentsituation to disengage a manual clutch. Several variables influence theamount of cable pull a control lever is capable of producing, including:lever pull, the linear distance from the lever pivot axis L to the cableanchor and the linear distance from the lever pivot axis L to the fingergrip portion 88 of the lever 52.

The “lever pull” is defined as the linear distance the finger gripportion 88 of the lever 52 is capable of moving toward the handlebaraxis H. The amount of lever pull is limited primarily by the distancethat the finger grip portion 88 can be placed away from the handlebaraxis H and remain comfortable for the average rider to grasp with one ormore fingers. This is commonly referred to as the “reach” of the lever.Obviously, this value may vary, however in practice the reach does notusually exceed about 3 inches. Accounting for the average thickness of ahandlebar 50 and handgrip 51 combination, the lever pull isapproximately 2⅜ inches at a theoretical maximum. However, thetheoretically available lever pull is not often realized in off-roadmotorcycling because it is impractical, and often unsafe, for a rider toremove all four fingers from the handgrip 51 to actuate the lever 52.Typically, a rider will use one or two fingers to actuate the clutchlever 52 while constantly maintaining a grip on the handlebar 50 withthe remaining fingers. In this scenario, the lever pull is limited bythe finger grip portion 88 of the lever 52 striking the fingersremaining on the handlebar. This value may also vary widely, however inpractice the maximum useful lever pull available is approximately one(1) inch when using one or two fingers to actuate the control lever 52.Additionally, it is desirable to have the lever pull be at a minimum inorder to allow the rider to shift gears quickly.

A second variable affecting the amount of cable pull in a control lever52 is the linear distance between the cable anchor and the lever pivotaxis L (cable distance). The amount of cable pull increases for a givenlever pull as the linear distance between the cable anchor and the leverpivot axis L increases. However, practical concerns restrain thisdistance from becoming too great. For example, increasing the distancebetween the cable anchor and the lever pivot axis L necessarilyincreases the amount the lever assembly 52 protrudes from the handlebaraxis H, increasing the chances of breaking the lever assembly 52, or acomponent thereof, in the event of a crash. Additionally, due to therotational movement of the cable anchor around the lever pivot axis L,increasing the linear distance between them increase the rotationalelement of the cable anchor's movement which, in turn, increases thefriction between the control cable 122 and its housing. Both results areespecially undesirable in off-road motorcycling, and off-road motorcycleracing in particular. In practice, and in the illustrated embodiment,the cable distance is approximately one (1) inch.

A third variable influencing the cable pull of a control lever 52 is thelinear distance between an inner edge of the finger grip portion 88 andthe lever pivot axis L (lever distance). Increasing this distancereduces the effective cable pull of a control lever 52. In practice, andin the illustrated embodiment, a typical lever distance is approximately2½ inches. In a multi-pivot design, such as that illustrated by Warrenet al., the lever distance is increased to approximately 3½ inches, inorder to accommodate the multiple pivot assemblies. With considerationof the practical constraints on the other variables influencing cablepull, as discussed immediately above, the performance of the lever 52 isoptimized by reducing the distance between the finger grip portion 88and the lever pivot axis L. This can be best illustrated by creating anequation describing the relationship between the cable pull, the cabledistance, the lever pull and the lever distance.

As a result of the cable anchor and the finger grip portion 88 bothrotating about the lever pivot axis, the ratio of the lever pull to thelever distance is equivalent to the ratio of the cable pull to the cabledistance. In terms of the cable pull, the equation becomes: cablepull=cable distance*(lever pull/lever distance). A table is constructedillustrating the effect that changing the lever distance has on theamount of cable pull. The standard values of one (1) inch for both thelever pull and the cable distance are used for the sake of comparison,and for the practical reasons described above.

LEVER DISTANCE CABLE PULL Δ (inches) (inches) (%) 2.5 0.40 — 3.0 0.3320.0 3.5 0.29 40.0 4.0 0.25 60.0 4.5 0.22 80.0

As illustrated in the table, the cable pull becomes greater as the leverdistance is decreased. The preferred lever distance of approximately 2½inches achieves a 20% increase in cable pull over a similar constructionhaving a ½ inch increase in lever distance. The increase in cable pullover a construction, such as illustrated by Warren et al., having anincrease of one (1) inch in lever distance is 40%. A 60% increase incable pull is achieved over a similar construction in which the leverdistance is increased by only 1½ inches.

The construction of preferred embodiments of the present inventionadvantageously retains a similar lever distance to that of aconventional control lever thereby providing a similar amount of cablepull as a conventional lever. This produces advantages over the morecomplex folding lever designs, which necessarily increase the leverdistance. As the lever distance increases, a greater amount of leverpull is required to achieve a cable pull sufficient to disengage theclutch, which results in increased time to shift gears. This results invaluable time lost for each shift during the course of a race and hasprevented previous folding lever designs from being practical for moreserious off-road motorcyclists. Additionally, if the increase in thelever distance is too great, it may no longer be possible to disengagethe clutch without pulling the lever 52 all the way to the handlebar 50.This would require the rider to completely release his grip of thehandlebar 50 with his fingers in order to shift the transmission. Thisalso inhibits the more complex folding lever designs from beingpractical for more than light off-road use.

In addition to performing control functions equivalently to conventionalcontrol levers, preferred embodiments of the present inventionadvantageously inhibit damage or breakage in the event of the motorcycle30 overturning or crashing. As mentioned previously, the front wheel 42,front suspension and handlebar 50 are journalled for rotation about asteering axis of the frame 34 from a neutral position, with the frontwheel 42 pointing straight ahead, to a rotated position approximately43-45° from the neutral position in each direction. Additionally, theend surface of the handlebar grip 51, a portion of the front wheel 42and a rear portion of the motorcycle 30 define a plane. If themotorcycle is overturned on substantially flat ground, the describedplane will substantially correspond with the ground. The rear portion ofthe motorcycle 30 that defines a point in the plane will vary dependingon the specific geometry of the motorcycle 30, but will likely includeone of the following components: the footpeg 54, the swingarm 38, therear wheel 36 or the side panel 66. Advantageously, in preferredembodiments of the control lever 52, the lever section 72 is capable ofdeflecting about its deflection axis D so as to be located between themotorcycle 30 and the described plane (or ground) in order to reduce thelikelihood of damage to the lever 52. In a presently preferredembodiment, the deflection axis D is located between the inner edge ofthe finger grip portion 88 and the lever pivot axis L when movinggenerally coaxial to the handlebar axis H, and the lever pivot axis Land a leading edge of the intermediate section 70 when moving generallynormal to the handlebar axis H.

A deflection distance of the lever section 72 is defined by the normaldistance between a first line extending perpendicular to the handlebaraxis H through the center of the ball end 92 in its normal position anda second line extending perpendicular to the handlebar axis H throughthe center of the ball end in its fully deflected position. An increasein the deflection distance results in an increase in the ability of thelever section 72 to deflect inward of the defined plane, and thereforecontinue to deflect in response to a force input from the ground withoutreaching its fully deflected position. The deflection distance isinfluenced by the linear distance from the lever pivot axis L to theball end 92 (lever length) and the angular rotation of the lever section72 from its normal position to its fully deflected position (deflectionangle). An increase in the deflection angle results in an increaseddeflection distance. A reduction in lever length (e.g., the deflectionpivot moving toward the ball end 92) results in a reduced deflectiondistance for a given deflection angle.

The lever length may vary widely, however it is typically desirable forthe ball end 92 to be substantially proximate the end surface of thehandlebar grip 51. Such a construction increases the effective length ofthe finger grip portion 88 of the lever 52 and allows the rider of themotorcycle 30 convenient access to the finger grip portion 88 throughouta wide range of hand positions on the handgrips 51. A typical leverlength to achieve these goals is approximately 5½ inches. Desirably, thelever section 72 does not significantly extend beyond the end surface ofthe handgrip 51 and desirably is no longer than ¾ inches beyond the endsurface of the handgrip 51. Accordingly, the lever is desirably between3 inches and 6½ inches in length.

The likelihood of damage to the lever 52, and therefore the desireddeflection distance of the lever section 72, in the event of themotorcycle 30 overturning depends at least in part on the angularposition of the handlebar 50 when the left side of the motorcyclestrikes the ground. Assuming the clutch lever 52 is mounted on itstypical position on the left side of the handlebar 50, the risk ofdamage is slightest when the handlebar 50 is fully rotated to the rightof its neutral position. The likelihood of damage to the clutch lever 52is increased if the motorcycle 30 strikes the ground with the handlebar50 in its neutral position. In this situation, a deflection angle ofapproximately 80-90°, with a lever length of 5½ inches, may besufficient to prevent damage to the control lever 52.

The likelihood of damage to the clutch control lever 52 is perhapsgreatest if the motorcycle 30 strikes the ground with the handlebar 50fully rotated to the left side of its neutral position. In thissituation, a deflection angle of at least approximately 120° ispreferred. Advantageously, the illustrated embodiment in FIGS. 2-5provides a deflection angle of approximately 132° with a lever length of5½ inches. The increased deflection angle provides a safety factoruseful in the event that a portion of the ground on which the motorcycle30 overturns is uneven or irregular.

The table below illustrates the change in deflection distance for agiven change in the deflection angle. The table shows values for a leverassembly having a lever length of 5½ inches. As illustrated in thetable, a collapsible lever constructed similarly to the above-describedembodiment has a deflection distance 66.9% greater than a folding levercapable of only 90° of angular rotation.

% % DEFLECTION DEFLECTION IMPROVEMENT IMPROVEMENT ANGLE DISTANCE FROM90° FROM 100° (degrees) (inches) (%) (%)  90 5.50 — — 100 6.46 17.4 —110 7.38 34.2 14.3 120 8.25 50.0 27.7 132 9.18 66.9 42.1 141 9.77 77.751.3

With reference to FIGS. 6-8, a second preferred embodiment of a manualclutch control lever 52 will now be described. The embodimentillustrated in FIGS. 6-8 is similar in structure and function to thepreviously described embodiment, therefore the same reference numeralswill be used to identify substantially equivalent structures, whereappropriate.

FIG. 7 shows the pivot portion 90 of the lever section 72 comprising apair of flange sections 126. The flanges 126 of the lever section 72 arespaced apart to accommodate the flange sections 86 of the intermediatesection 70. A deflection pivot bolt 104, defining a deflection axis D,is passed through corresponding apertures in the lever section 72 andthe intermediate section 70. The lever section 72 is fixed substantiallycoaxially to the bolt 104 through a pair of roller bearings 128. Thus,the lever section 72 is capable of rotation relative to the intermediatesection 72 about the deflection axis D. Obviously, the roller bearings128 may be replaced by a different type of bearing, a bushing or omittedaltogether. The biasing member 108, primarily comprising a torsionspring 112, is mounted between the flanges 86 of the intermediatesection 70, substantially coaxially with the deflection axis D and isseparated from the bolt 104 by a bushing 130. A nut 110 secures the bolt104 in place.

The operation of the control lever 52 illustrated in FIGS. 6-8 issimilar to the function of the previously described embodiment. For useas a control lever, one end of the biasing member 118 engages the leversection 72 and the other end engages the intermediate section 70,biasing the lever section 72 to a normal position (FIG. 6). Similarly tothe previous embodiment, to operate the control lever 52, the engagesthe finger grip portion 88 of the lever section 72 to rotate the lever52 toward the handlebar 50. The reach bolt 96 transfers the force inputof the lever section 72 into the intermediate section 70, causing theintermediate section 70 to rotate about the lever pivot axis L toachieve an actuated position. This action exerts a pulling force on thecontrol cable 122 and, in the present situation, disengages a manualclutch.

FIG. 8 illustrates the lever section 72 of the control lever assembly 52in a fully deflected position. The illustrated embodiment is capable ofachieving a deflection angle of approximately 141° and has a leverlength of 5½ inches, resulting in a slightly greater deflection distancethan the first illustrated preferred embodiment. Additionally, theenlarged flanges 126 of the lever section 72 add strength to thedeflection pivot and the entire lever assembly 52.

FIG. 9 illustrates a preferred embodiment for use with a hydraulicclutch assembly. The handlebar mount 68 and intermediate section 70 aremodified such that rotation of the intermediate section 70 results in anactuating surface 132 exerting a pushing force on a hydraulic mastercylinder plunger 134.

Although the present invention has been described in terms of a certainembodiment, other embodiments apparent to those of ordinary skill in theart also are within the scope of this invention. Thus, various changesand modifications may be made without departing from the spirit andscope of the invention. For instance, various components may berepositioned as desired. Moreover, not all of the features, aspects andadvantages are necessarily required to practice the present invention.Accordingly, the present invention is not intended to be limited by therecitation of preferred embodiments, but is intended to be definedsolely by the reference to the appended claims.

What is claimed is:
 1. A control lever assembly for use with a vehiclecontrol system that includes a handlebar defining a handlebar axis, thehandlebar having at least one hand grip, a lever mount mounted to thehandlebar and being configured to pivotally support said control leverassembly about a primary pivot axis, said control lever assemblycomprising: a lever section defining a hand contact portion; anintermediate section, said intermediate section coupling said leversection to said mount, said lever section being located alongside saidhand grip and supported for pivotal motion toward or away from said handgrip around a secondary pivot axis defined by said intermediate section,said secondary pivot axis being substantially transverse to saidhandlebar axis; a biasing assembly configured to bias said lever sectiontoward said hand grip; an abutment surface on said intermediate sectionconfigured to limit the motion of said lever section by said biasingassembly, said lever section being deflectable from its normal positionin a direction away from said hand grip; wherein said biasing assemblycomprises a spool mounted on said intermediate section on said secondaryaxis, and a torsion spring wound on said spool, said torsion springhaving a first end and a second end, said first end being anchored tosaid spool and said second end being anchored to the lever section. 2.The control lever assembly of claim 1, additionally comprising a boltpassing through aligned openings in said intermediate section and saidlever section and defining said secondary pivot axis, said spool havinga central hole therein receiving said bolt, whereby the bolt secures thespool to the intermediate section.
 3. The control lever assembly ofclaim 2, wherein said spool has a central recess communicating with saidcentral hole, said bolt terminating within said central recess.
 4. Thecontrol lever assembly of claim 2, wherein said intermediate section hastwo parallel ear portions, said lever section having a tongue extendinginto the space between said parallel ear portions, said aligned openingsbeing formed in said ear portions and said tongue.